Publication details

Heterometallic 3d-4f {Co2Gd4} phosphonates: new members of the potential magnetic cooler family

Authors

DOROSHENKO Iaroslav BUCHHOLZ Axel BERGEROVA Eva Domincova PLASS Winfried PINKAS Jiří

Type Article in Periodical
Magazine / Source New Journal of Chemistry
MU Faculty or unit

Faculty of Science

Citation
Web http://dx.doi.org/10.1039/c9nj05071j
Doi http://dx.doi.org/10.1039/c9nj05071j
Keywords TRANSITION-METAL-COMPLEXES; CLUSTERS; CAGES; GD; SYMMETRY; SHAPE; LANTHANIDES; DESIGN; LN
Description Three new heterometallic phosphonate complexes with a novel 3d-4f metal core {Co2Gd4} were isolated. The reactions between CoCl2, GdCl3, ligand sodium salts, and 2,2 '-bipyridine in methanol solution lead to new unexpected 3d-4f heterometallic complexes, [Na(2)CoIII2Gd(4)(L)(6)(bpy)(2)(OR)(2)]center dot nSolv (L = SAA(3-) (1), BSAA(3-) (2), and NAA(3-) (3); bpy = 2,2 '-bipyridine; OR = OH and OMe; Solv = H2O and MeOH), composed of a rare case of two magnetically independent oxygen bridged Gd2O2 dinuclear units, which are separated by O-P-O bridges. According to the BVS calculations and measured magnetic properties, only Co-III ions are present in the obtained complexes. The magnetic properties of the compounds 1-3 were studied and the entropy changes for the designation of the magnetocaloric effect were calculated. The largest value for the magnetic entropy change -Delta S-M of 20 J kg(-1) K-1 for complex 1 has been found for T-av = 2.25 K and H-f = 5 T.
Related projects: